1. Field of the Invention
This invention relates to a data communication system having an automatic dialing function, and more specifically, relates to a method of automatically dialing a telephone number in a facsimile system having a telephone handset incorporated therein, when using an information service.
2. Description of the Related Art
A typical automatic route selection (ARS) function in an information communication system such as a facsimile system having a telephone handset is to provide a variety of information services such as retrieving, inquiring, and reading out information from an automatic answer control system when a subscriber's communication terminal is connected to the automatic answer control system through a telephone line. The user can retrieve, inquire, or read out information by following a guidance message provided by the automatic answer control system when using the information service. Generally, there are two techniques of servicing information in the automatic answer control system. The first method relates to a way in which the next service information is progressed when any key is input in the middle of the reproduction of a guidance message. The second method relates to a way in which the next service information is progressed when any key is input after completion of the playback of guidance message.
When the subscriber wants the information service, and the service is one that progresses to the next procedure when any key is input in the middle of reproducing the guidance message, the subscriber can input numeral keys according to the guidance message, using an automatic dialing function of the telephone handset such as one-touch dialing, speed dialing, and redialing functions as disclosed, for example, in U.S. Pat. No. 5,506,895 for Telephone Apparatus With Automatic Dialing Function issued to Hirai et al., U.S. Pat. No. 5,473,674 for Data Communication Apparatus Having An Auto-Dialing Function issued to Maeda, U.S. Pat. No. 5,289,533 for Facsimile Transmitting and Receiving Apparatus issued to Wasio et al., U.S. Pat. No. 5,216,705 for Data Communication Apparatus With Abbreviated Dial Key Having A Plurality Of Dial Data And Capable Of Selecting One Of Two Communication Functions issued to Yoshida et al., U.S. Pat. No. 5,134,653 for Automatic Dialing Machine issued to Satomi et al., and U.S. Pat. No. 4,920,560 for Method Of Automatic Dialing And Automatic Dialing Device For Facsimile Apparatus issued to Kayeyama. However, the subscriber cannot use the automatic dialing function when the information service is designed such that it requires the guidance messages to be completed before the next procedure can be requested. This service requirement often causes the codes entered according to the guidance message, to be input irregularly.
In the conventional automatic dialing function of the facsimile system having a telephone handset incorporated therein, dial signals are sequentially transmitted, and transmission interval of each pulse is fixed to three seconds, so that the user must calculate the transmission interval of pulses when registering a telephone number for performing an automatic dialing function. This manual operation interferes with accurate registration of the telephone number. Thus, the user cannot utilize some information services with automatic dialing functions because the automatic answer control system requires too long an interval between pulses.